Match the tube to the cooling water
The tube-side fluid usually picks the alloy. A quick guide from twenty years of retube quotes:
| Cooling water | First choice | Step up |
|---|---|---|
| Fresh, clean, low chloride | SA179 carbon steel, C12200 copper | TP304L |
| Fresh, treated, some ammonia | C44300 admiralty (if ammonia is low), TP304L | TP316L, SA268 ferritic |
| Brackish or polluted | C70600 copper-nickel | C71500, SA789 duplex |
| Clean seawater, moderate velocity | C70600 copper-nickel | C71500 |
| Seawater, high velocity or sulfides | C71500, C72200 | Alloy 625, titanium |
| Chloride stress cracking history | SA789 duplex, SA268 ferritic | Alloy 825, C-276 |
If the process side is the problem rather than the water, tell us the fluid and temperature and we will work from that end.
Fabricator-friendly supply
- Cut-to-length and U-bends. Send the tube sheet drawing and bend schedule. We deliver finished tube tagged by row.
- Minimum wall or average wall. SB-111 tube is available either way. Say which one your design was calculated on.
- Ends and finish. Deburred, cleaned, and capped for immediate rolling. Stress-relieved ends on request.
- Mixed-alloy orders. Admiralty for the condenser, SA179 for the oil cooler, duplex for the produced water exchanger: one PO, one release, one truck.
Why Ameritube for exchanger tube
Our first big refinery order was 12,000 admiralty tubes for Exxon Mobil and Petrobras exchangers, with zero customer rejections. Since then we have built the plant around exchanger tube: a 60-foot annealing furnace, eddy current on every tube, hydrostatic and ammonia vapor testing on request, and now our own melt and cast so the copper alloys are American from the furnace. Read the case studies for the U-bend and retube jobs that came after.
What to include in your RFQAlloy, OD, wall (state minimum or average), straight length or U-bend schedule with radii, quantity in pieces, temper, the governing spec (SB-111, SA179, SA213, and so on), tube sheet material if you want a compatibility check, and any customer-specific testing or MTR format.